Antibiotic prophylaxis by dentists for the prevention of bacterial endocarditis is a well established therapeutic regimen. However, whether clinicians are aware of the need for such therapy and what proportion is aware of the specific recommendations of experts are matters for speculation alone. We plan to develop and pre-test an instrument which will provide information concerning level of knowledge among dentist-clinicians. Demographic information and information concerning case-finding practices of dentists will also be collected. Because we want to examine the influence of professional integration and education on awareness of the problem and levels of knowledge concerning proper management of patients at risk for bacterial endocarditis, we will obtain data from stratified random samples of three groups: general practioners in a rural setting, general practioners in an urban setting, and oral surgeons. In addition to professional integration and education, other independent variables which we plan to use have been utilized in many other studies of innovation diffusion and utilization of scientific knowledge. They include size of work unit, orientation toward change, commercial orientation, and scientific orientation, among others. Data analysis will include 1) exploration of the measurement constructs with respect to inter-rater reliability, internal consistency reliability, and validity, and 2) exploration of the phenomena, i.e., frequency distributions of the variables in the study populations, the association of individual variables, and the use of one-way analysis of variance to test potential differences among groups. Finally, multiple regression will be used to supplement ANDVA, in order to develop predictive equations to examine the effect, size, and significance of independent variables on the dependent variable.